It has been recognized that many of the minor and major traumatic conditions of the foot, leg and knee can be caused by the misalignment of the joints in the foot. These conditions can be hereditary such as the presence of a longer or shorter leg, can be acquired through traumatic injury or can be caused by repetitive stress or strain on the joints experienced during industrial or athletic activity.
Misalignment of the foot can cause minor trauma such as inflammation, blisters, rashes, calluses, corns, ingrown toe nails or more aggravated conditions such as bunions or bone spurs, typically in the heel area. Over-the-counter insoles are available to relieve minor discomfort. However, they are available in fixed sizes and thicknesses. It is possible to reduce discomfort and promote healing of inflamed areas by custom-cutting thick cushioning products such as Moleskin.RTM. into pads which can be locally adhered to the traumatic area or adjacent to the traumatic area. Pads and insoles only treat the symptoms of the misalignment and simply reduce irritation and attempt to prevent further trauma by reducing pressure, rubbing, or abrasion on the sensitive area of the foot. Sometimes surgery is utilized to remove the calluses, corns or bunions.
A more scientific approach has been to develop customized biomechanical devices that are intended to correct the misalignment of the joints. These devices, known as orthotics, are prescribed by medical specialists such as orthopedic doctors, podiatrists or doctors specializing in sports medicine. After extensive physical measurements of the patient, a plaster impression of the foot is taken. The orthotic is manufactured from the impression to specifications provided by the doctor as to the degree of pronation correction required. A soft layer of foam can be applied to the top or bottom surface of the orthotic to provide comfort and to prevent the orthotic from sliding when in a shoe.
Orthotics are very expensive, on the order of several hundred dollars a pair. Since they are so expensive, they are usually designed to provide the final correction. The degree of correction can be so severe that the orthotic causes such pain and discomfort to the patient, that it discourages usage of the orthotic and eventually it is no longer used. It is not possible to adjust the fit of the hard plastic orthotic.